Transparent conductive films, articles, and methods

ABSTRACT

Transparent conductive films, articles made from them, and methods of making them are disclosed. Some transparent conductive films include flexible glass substrates and conductive layers containing metal nanoparticles. Others include at least one layer with cell walls that contain metal nanorods or conductive nanowires. Still others include a substrate with a coating disposed on it, with the coating including conductive components and photopolymers. Such films are useful in such articles as electronic displays, touch screens, and the like.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.13/042,101, filed Mar. 7, 2011, which claimed priority from U.S.Provisional Application No. 61/310,828, filed Mar. 5, 2010, U.S.Provisional Application No. 61/310,891, filed Mar. 5, 2010, and U.S.Provisional Application No. 61/310,898, filed Mar. 5, 2010, which arehereby incorporated by reference in their entirety.

SUMMARY

At least one first embodiment provides a transparent conductive filmcomprising a flexible glass substrate and at least one conductive layerdisposed on the flexible glass substrate, where the at least oneconductive layer comprises at least one metal nanoparticle.

In at least some embodiments, the flexible glass substrate has anaverage thickness less than about 500 μm, or less than about 150 μm, orless than about 100 μm, such as, for example, an average thicknessgreater than about 10 μm and less than about 100 μm. In at least someembodiments, the flexible glass substrate can achieve a radius ofcurvature greater than about 5 mm and less than about 50 cm withoutbreaking, such as, for example, a radius of curvature greater than about10 mm and less than about 10 cm without breaking. The flexible glasssubstrate may, for example, comprise an ion-exchanged glass. In at leastsome embodiments, the flexible glass substrate comprises at least onecompression stress layer. The flexible glass substrate may, for example,comprise at least one of a silicate glass, an alkali silicate glass, analkali aluminosilicate glass, an aluminosilicate glass, a borosilicateglass, an alkali aluminogermanate glass, an alkali germanate glass, oran alkali gallogermanate glass.

In at least some embodiments, the at least one metal nanoparticlecomprises at least one nanowire, nanocube, nanorod, nanopyramid, ornanotube, or the at least one metal nanoparticle comprises at least onenanowire. The at least one metal nanoparticle may, for example, compriseat least one coinage metal, such as, for example, silver.

In at least some embodiments, the at least one conductive layer has asurface resistivity of less than about 150 ohms/sq, or less than about125 ohms/sq, or less than about 100 ohms/sq, or less than about 75ohms/sq, or less than about 65 ohms/sq, such as, for example, a surfaceresistivity of about 110 ohms/sq or a surface resistivity of about 60ohms/sq.

In at least some embodiments, the transparent conductive film has atotal light transmission of at least about 80%, or of at least about85%. Or the transparent conductive films have ASTM D1003 haze values ofless than about 10%, such as, for example, haze values of about 9.38% orhaze values of about 5.22%.

In at least some embodiments, the transparent conductive film furthercomprises at least one layer disposed between the flexible glasssubstrate and the at least one conductive layer.

At least one second embodiment provides an article comprising atransparent conductive film comprising a flexible glass substrate and atleast one conductive layer disposed on the flexible glass substrate,where the at least one conductive layer comprises at least one metalnanoparticle. In some embodiments, such an article may comprise anelectronic display, a touch screen, or the like. Such an article may,for example, comprise a portable telephone, a cellular telephone, acomputer display, a laptop computer, a tablet computer, apoint-of-purchase kiosk, a music player, a television, an electronicgame, an electronic book reader, or the like.

At least one third embodiment provides a method comprising providing aflexible glass substrate and coating the flexible glass substrate withat least one composition comprising at least one nanoparticle. In atleast some embodiments, the flexible glass substrate is provided on aroll.

At least some embodiments provide the coated flexible glass substrateproduced by such methods.

At least some embodiments provide such methods that further compriseforming a transparent conductive film from the coated flexible glasssubstrate.

At least some embodiments provide the transparent conductive filmproduced by such methods.

These and other embodiments will be understood from the description, theexamples, and the claims that follow.

DESCRIPTION

U.S. application Ser. No. 13/042,101, filed Mar. 7, 2011, U.S.Provisional Application No. 61/310,828, filed Mar. 5, 2010, U.S.Provisional Application No. 61/310,891, filed Mar. 5, 2010, and U.S.Provisional Application No. 61/310,898, filed Mar. 5, 2010, are herebyincorporated by reference in their entirety.

Transparent Conductive Films

Transparent conductive films have commonly comprised polymericsubstrates, which can be flexible and amenable to continuous web coatingmanufacturing technologies. However, polymeric substrates are often hazyand can develop physical defects, such as surface scratches and scuffs,which can affect transparency. Glass, in contrast, can provide goodtransparency, but because of its typical poor flexibility, has commonlybeen processed batchwise. The products of such batch processes can bemore costly and less uniform than those than those made using continuousprocesses.

Applicants disclose and claim embodiments that provide transparentconductive films comprising flexible glass substrates on which one ormore conductive coating layers are disposed. Such transparent conductivefilms can be amenable to continuous web coating manufacturingtechnologies, while also being more scratch-resistant and more opticallytransparent than films comprising polymeric substrates. Such transparentconductive films can be suitable for such applications as electronicdisplays, touch screens, or other elements that may make up such devicesas portable telephones, cellular telephones, computer displays, laptopcomputers, tablet computers, point-of-purchase kiosks, music players,televisions, electronic games, electronic book readers, and the like.

The transparent conductive films may have a total light transmission ofat least about 80%, or of at least about 85%. Or the transparentconductive films may have ASTM D1003 haze values of less than about 10%,such as, for example, haze values of about 9.38% or haze values of about5.22%.

Flexible Glass Substrates

Some embodiments comprise flexible glass substrates. The flexible glasssubstrates may, for example, comprise at least one of a silicate glass,an alkali silicate glass, an alkali aluminosilicate glass, analuminosilicate glass, a borosilicate glass, an alkali aluminogermanateglass, an alkali germanate glass, an alkali gallogermanate glass, or thelike. Commercially available flexible glass substrates include, forexample, glasses marketed by Corning under the GORILLA® trade name andglasses marketed by Asahi Glass under the DRAGONTAIL™ trade name.

Ion-Exchanged Glass and Compression Stress Layers

Such flexible glass substrates may, for example, comprise anion-exchanged glass. By replacing some of the alkali metal ions in theglass with differently sized ions, at least a portion of the glasssubstrate can become compression stress hardened, for example, in acompression stress layer. Such ion-exchanged glass compositions aredescribed in, for example, U.S. Pat. No. 6,333,285 to Chopinet et al.,granted Dec. 25, 2001; U.S. Pat. No. 6,518,211 to Bradshaw, et al.,granted Feb. 11, 2003; U.S. Pat. No. 7,309,671 to Kurachi et al.,granted Dec. 18, 2007; U.S. Patent Application Publication 2009/0197088,published Aug. 6, 2009; U.S. Patent Application Publication2009/0220761, published Sep. 3, 2009; U.S. Patent ApplicationPublication 2009/0298669, published Dec. 3, 2009; and U.S. Pat. No.7,666,511 to Ellison et al., granted Feb. 23, 2010, each of which ishereby incorporated by reference in its entirety.

Substrate Thicknesses and Radii of Curvature

In at least some embodiments, the flexible glass substrate has anaverage thickness less than about 500 μm, or less than about 150 μm, orless than about 100 μm, such as, for example, an average thicknessgreater than about 10 μm and less than about 100 μm. In at least someembodiments, the flexible glass substrate can achieve a radius ofcurvature greater than about 5 mm and less than about 50 cm withoutbreaking, such as, for example, a radius of curvature greater than about10 mm and less than about 10 cm without breaking. For the purpose ofthis application, to “achieve a radius of curvature without breaking” isto have the glass substrate survive intact when being bent from a firstradius of curvature larger than the claimed range to a second radius ofcurvature contained within the claimed range.

Some such substrates may be stored and supplied on rolls suitable foruse in continuous web coating manufacturing. Processes for manufacturingsuch glass substrates are described in, for example, U.S. Pat. No.7,677,058 to Hawtof et al., granted Mar. 16, 2010; U.S. PatentApplication Publication 2010/0107694, published May 6, 2010; U.S. PatentApplication Publication 2010/0291346, published Nov. 18, 2010; and U.S.Patent Application Publication 2010/0319401, published Dec. 23, 2010,each of which is hereby incorporated by reference in its entirety.

Conductive Layers

At least some embodiments provide at least one conductive layer disposedon the flexible glass substrate. Such conductive layers may comprise atleast one metal nanoparticle. For the purpose of this application, ananoparticle is an object with at least one dimension less than about100 nm. Examples of nanoparticles include nanowires, nanocubes,nanorods, nanopyramids, nanotubes, and the like. Conductive layerscomprising nanowires are described in, for example, European PatentApplication Publication EP 1 965 438, published Sep. 3, 2008, which ishereby incorporated by reference in its entirety. Nanoparticles may beconstructed from any of a variety of metals, such as, for example,coinage metals, including silver, gold, copper, and the like. In atleast some embodiments, the at least one conductive layer may comprise aconductive network of nanoparticles, such as, for example, a conductivenetwork of nanowires. The concentration of such nanoparticles in the atleast one conductive layer is preferably sufficiently high to comprisesuch a conductive network. While not wishing to be bound by theory, sucha concentration may, for example, be higher than a percolation thresholdfor the at least one conductive layer.

The at least one conductive layer may optionally comprise one or morepolymers, copolymers, or oligomers, such as, for example, acrylicpolymers, vinyl polymers, polyesters, polycarbonates, styrenic polymers,polyurethanes, polyolefins, epoxy polymers, cellulosic polymers,silicone polymers, phenolic polymers, fluoropolymers, rubbers,conductive polymers, semiconductive polymers, nonconductive polymers,and the like. The concentration of such polymers, copolymers, oroligomers is preferably low enough not to reduce the conductivity of thelayer below that required for the intended application.

The at least one conductive layer may optionally comprise other additivecomponents, such as corrosion inhibitors, viscosity modifiers,surfactants, and the like. These and other additive components will beunderstood by those skilled in the art. The concentration of suchadditives is preferably low enough not to reduce the conductivity of thelayer below that required for the intended application.

In at least some embodiments, the at least one conductive layer has asurface resistivity of less than about 150 ohms/sq, or less than about125 ohms/sq, or less than about 100 ohms/sq, or less than about 75ohms/sq, or less than about 65 ohms/sq, such as, for example, a surfaceresistivity of about 110 ohms/sq or a surface resistivity of about 60ohms/sq. Surface resistivity may, for example, be measured using anR-CHEK™ RC2175 four-point resistivity meter.

Other Layers

In at least some embodiments, the transparent conductive film furthercomprises at least one layer disposed between the flexible glasssubstrate and the at least one conductive layer. Such a layer may, forexample, might be provided to improve adhesion between the flexibleglass substrate and the at least one conductive layer.

Or the transparent conductive film might, for example, further compriseat least one layer disposed on the at least one conductive layer. Suchlayers might comprise electronic device functional layers, such as, forexample, active layers for organic photovoltaic devices or active layersfor organic light emitting diodes. Or they might comprise structurallayers, such as, for example, overcoat layers.

Or the transparent conductive film might, for example, further compriseat least one layer disposed on the side of the flexible glass substrateopposite that which the at least one conductive layer is disposed. Suchlayers comprise, for example, additional conductive layers, backcoatlayers, electronic device active layers, structural layers, and thelike.

Articles Comprising Transparent Conductive Films

Some embodiments provide articles comprising transparent conductivefilms of the at least one first embodiment. Such articles may, forexample, comprise electronic displays, touch screens, and the like, foruse in such applications as portable telephones, cellular telephones,computer displays, laptop computers, tablet computers, point-of-purchasekiosks, music players, televisions, electronic games, electronic bookreaders, and the like. These and other such articles will be understoodby those skilled in the art.

Fabrication Methods and Product Films

Some embodiments provide methods comprising providing a flexible glasssubstrate and coating the flexible glass substrate with at least onecomposition comprising at least one nanoparticle. The flexible glasssubstrate may, for example, be provided on a roll. Other embodimentsprovide the coated flexible glass substrates produced by such methods.Such coated flexible glass substrates may, for example, be taken up onrolls and supplied from rolls for further processing. Still otherembodiments provide such methods that further comprise forming atransparent conductive film from the coated flexible glass substrate.Yet other embodiments provide the transparent conductive films producedby such methods. Such transparent conductive films may, for example, betaken up on rolls for storage, distribution, sale, or furtherprocessing.

Such methods may comprise disposing one or more coating mixes on theflexible glass substrate to form one or more coating layers, such as,for example, one or more conductive layers. The various coating mixesmay use the same or different solvents, such as, for example, water ororganic solvents. Layers may be coated one at a time, or two or morelayers may be coated simultaneously, for example, through use of slidecoating.

Layers may be coated using any suitable methods, including, for example,dip-coating, wound-wire rod coating, doctor blade coating, air knifecoating, gravure roll coating, reverse-roll coating, slide coating, beadcoating, extrusion coating, curtain coating, and the like. Examples ofsome coating methods are described in, for example, Research Disclosure,No. 308119, December 1989, pp. 1007-08, (available from ResearchDisclosure, 145 Main St., Ossining, N.Y., 10562,http://www.researchdisclosure.com), which is hereby incorporated byreference in its entirety.

Such methods may comprise drying one or more coated layers, using avariety of known methods. Examples of some drying methods are describedin, for example, Research Disclosure, No. 308119, December 1989, pp.1007-08, (available from Research Disclosure, 145 Main St., Ossining,N.Y., 10562, http://www.researchdisclosure.com), which is herebyincorporated by reference in its entirety.

Such methods may be executed batchwise, semicontinuously, orcontinuously. Materials used in such methods may, for example, besupplied in roll form. Intermediate materials may, for example, be takenup and stored in roll form for later processing. Products may, forexample, be taken up and stored in roll form, suitable for suchactivities as inventorying, distribution, sale, or further processing.In some cases, intermediates or end products may be reduced in size fromtheir web-based form, using such methods as slicing, punching, cutting,and the like. It will be understood that, in many cases, continuous orsemicontinuous processing of web-based materials supplied from or takenup on rolls may decrease production costs and increase uniformity of theintermediates and products produced from such methods, relative to thoseproduced purely batchwise.

Cellular Structured Films and Methods

Some embodiments provide transparent conductive films comprising asubstrate and at least one layer disposed in the substrate, the at leastone layer comprising cell walls, where the cell walls comprise one ormore of conductive nanorods, conductive nanowires, or conductivenanotubes.

A method of forming such a layer is described in PCT Patent PublicationWO 2003/106573, published Dec. 24, 2003, which is hereby incorporated byreference in its entirety. A coating mixture comprising metalnanopowders, volatile solvents, and polymers is disposed on a substrate,after which the volatile solvent is evaporated. The resulting coatingexhibits a two-dimensional cellular foam structure. Because of theapproximately spherical shape of the metal nanopowders, a highconcentration is required to allow sufficient connectivity to allow thecellular structure to be conductive. Such high loadings of nanopowderslead to low transparency of the resulting film.

Layers may be coated using any suitable methods, including, for example,dip-coating, wound-wire rod coating, doctor blade coating, air knifecoating, gravure roll coating, reverse-roll coating, slide coating, beadcoating, extrusion coating, curtain coating, and the like. Examples ofsome coating methods are described in, for example, Research Disclosure,No. 308119, December 1989, pp. 1007-08, (available from ResearchDisclosure, 145 Main St., Ossining, N.Y., 10562,http://www.researchdisclosure.com), which is hereby incorporated byreference in its entirety.

Such methods may comprise drying one or more coated layers, using avariety of known methods. Examples of some drying methods are describedin, for example, Research Disclosure, No. 308119, December 1989, pp.1007-08, (available from Research Disclosure, 145 Main St., Ossining,N.Y., 10562, http://www.researchdisclosure.com), which is herebyincorporated by reference in its entirety.

Applicants employ nanorods or nanowires or nanotubes to provide improvedfilms. Polymer emulsions may also be employed, as well. Use of nanorods,nanowires, or nanotubes provides increased conductivity in the cellwalls of the foam structure. Without wishing to be bound by theory, itis believed that the higher aspect ratio of the nanorods, nanowires, andnanotubes relative to that of the nanopowders aids their alignmentduring cell wall formation. Equivalent conductivity may therefore beachieved at lower metal loadings, improving film transparency. Moreover,use of nanorods, nanowires, or nanotubes may allow elimination of hightemperature sintering required to increase the conductivity of thenanopowder-based formulations.

In at least some embodiments, the layer comprising cell walls furthercomprises voids at least partially surrounded by the cell walls. Suchvoids may be free of conductive nanorods, nanowires, and nanotubes. Suchvoids may, for example, be formed by volatilizing a solvent that has lowsolubility in the phase carrying the nanorods, nanowires, or nanotubes.

In some embodiments, the nanorods, nanowires, or nanotubes compriseconductive metal. In other embodiments, the nanorods, nanowires, ornanotubes comprise conductive carbon. In still other embodiments, bothconductive metals and conductive carbon may be used.

Still other embodiments provide such transparent conductive films, wherethe substrate is a flexible glass substrate.

Photopolymer Films and Methods

Some embodiments provide transparent conductive films comprising asubstrate and at least one layer disposed on the substrate, where the atleast one layer comprises conductive components and at least onephotopolymer composition. Such conductive components may, for example,comprise carbon nanotubes, metal nanoparticles, or the like. For thepurpose of this application, “photopolymer composition” refers to acomposition that is radiation curable to form a polymer. In at leastsome embodiments, such a photopolymer composition may be cured byexposure to, for example, ultraviolet radiation.

In at least some embodiments, the at least one layer may be produced bypreparing at least one coating mixture comprising the conductivecomponents and the at least one photopolymer composition, and coating asubstrate, such as, for example, a transparent substrate. Such a coatedsubstrate may, for example, be dried to form a transparent coated filmthat is radiation curable.

Layers may be coated using any suitable methods, including, for example,dip-coating, wound-wire rod coating, doctor blade coating, air knifecoating, gravure roll coating, reverse-roll coating, slide coating, beadcoating, extrusion coating, curtain coating, and the like. Examples ofsome coating methods are described in, for example, Research Disclosure,No. 308119, December 1989, pp. 1007-08, (available from ResearchDisclosure, 145 Main St., Ossining, N.Y., 10562,http://www.researchdisclosure.com), which is hereby incorporated byreference in its entirety.

Such methods may comprise drying one or more coated layers, using avariety of known methods. Examples of some drying methods are describedin, for example, Research Disclosure, No. 308119, December 1989, pp.1007-08, (available from Research Disclosure, 145 Main St., Ossining,N.Y., 10562, http://www.researchdisclosure.com), which is herebyincorporated by reference in its entirety.

Transparent conductive films are commonly coated on polymer substratesin order to achieve web coating capabilities and meet flexibilityrequirements of intended applications. Often, specific patterns ofconductive materials are desired, which can be achieved by etching atransparent conductive film in the pattern desired. For example,European Patent Publication EP 1947701, published Jul. 23, 2008, herebyincorporated by reference in its entirety, describes a method thatinvolves deposition of silver nanowires on a substrate followed by asecond coating step with a photopolymer layer overcoat. After curing ina pattern, the uncured portions are removed by differential adhesion.The overcoat may be removed with a strong base, such as described inU.S. Patent Application Publication 2008/0292979, published Nov. 27,2008, which is hereby incorporated by reference in its entirety.

In at least some embodiments, the photopolymer composition is waterdevelopable. Examples of such water developable photopolymercompositions include those that have been used in high resolutionlithographic applications, such as, for example, in the pre-sensitizedoffset printing plates that had been marketed by 3M under the HYDROLITH™trade name. Such plates are water resistant until exposed to patterningby radiation, after which the unexposed areas of the material on theplate can be removed using water. See, for example, U.S. Pat. No.4,401,743 to Incremona, issued Aug. 30, 1983, and U.S. Pat. No.4,408,532 to Incremona, issued Oct. 11, 1983, each of which is herebyincorporated by reference in its entirety.

Use of a water developable photopolymer composition allows coating anintegral single conductive layer that is radiation curable and waterdevelopable, without using a separate photopolymer layer overcoat, whilealso avoiding use of developing compositions comprising such chemicalsas strong bases. Such a water developable photopolymer composition maybe patterned by exposure to radiation, and may then be developed withwater to form a patterned conductive coating.

At least some embodiments provide such transparent conductive films,where the substrate is a flexible glass substrate.

Other embodiments provide methods comprising providing a conductive filmcomprising a substrate and at least one layer disposed on the substrate,where the at least one layer comprises conductive components and atleast one photopolymer composition; and exposing the transparentconductive film to radiation. Such a conductive film may, for example,be a transparent conductive film. Such a photopolymer composition may,for example, be water developable. Such a substrate may, for example, bea flexible glass substrate.

Other embodiments provide methods comprising providing a conductive filmcomprising a substrate and at least one coating disposed on thesubstrate, where the coating comprises conductive components and atleast one photopolymer composition; and developing the film to form apatterned conductive film. Such a patterned conductive film may, forexample, be a transparent patterned conductive film. Such a photopolymercomposition may, for example, be water developable. Such a substratemay, for example, be a flexible glass substrate.

EXAMPLES Materials

Unless otherwise noted, materials were available from Sigma-Aldrich,Milwaukee, Wis.

Bis(vinylsulfonyl)methane (BVSM) cross-linker was obtained from EastmanKodak.

CAB171-15 is a cellulose acetate butyrate polymer (Eastman Chemical).

DESMODUR® N3300 is an aliphatic polyisocyanate (hexamethylenediiosicyanate trimer) (Bayer).

GORILLA® 2317 is an alkali aluminosilicate glass (Corning).

LAROSTAT® 264A is an ethyl sulfate based cationic quaternary salt(BASF).

Gel-PB is a phthalated gelatin (Eastman Gelatine, Peabody, Mass.).

Silver nanowires had an average diameter of 90±20 nm and a length of20-60 μm (Blue Nano, Cornelius, N.C.).

Example 1

Solution A was prepared by adding 8.0 g of Gel-PB, 192 g of deionizedwater, and 0.04 g of 4-chloro-3,5-dimethylphenol to a flask that wasthen heated to 50° C. for 30 min with stirring.

To a 0.4 g aliquot of Solution A at 50° C. was added 0.7 g of deionizedwater, 0.016 g of a 1 wt % aqueous solution of LAROSTAT® 264A, 0.05 g ofa 1 wt % aqueous solution of BVSM, and 0.25 g of a 2.5 wt % silvernanowire dispersion in 2-propanol. The resulting mixture was mixed on awrist shaker to obtain a coating dispersion.

The coating dispersion was coated onto a GORILLA® 2317 flexible glasssubstrate using a #10 Mayer rod. The resulting coated substrate was diedin an oven at 107° C. for 6 min to obtain a transparent coated film.

The transparent coated film was evaluated for surface resistivity usingan R-CHEK™ RC2175 meter (Electronic Design to Market, Toledo, Ohio) andfor percent transmittance and haze according to ASTM D1003 using aHAZE-GARD PLUS Hazemeter (BYK-Gardner, Columbia, Minn.). These resultsare summarized in Table I.

Example 2

A coating dispersion was prepared by mixing at room temperature for 2min 100 parts by weight of CAB171-15 cellulose acetate butyrate polymer,29 parts by weight of N3300 isocyanate, 10 parts by weight of bismuthneodecanoate, 21 parts by weight of silver nanowires, 333 parts byweight of methyl ethyl ketone, 336 parts by weight of ethyl lactate, and315 parts by weight of isopropanol.

The coating dispersion was coated onto a GORILLA® 2317 flexible glasssubstrate using a #10 Mayer rod. The resulting coated substrate was diedin an oven at 107° C. for 6 min to obtain a transparent coated film.

The transparent coated film was evaluated for surface resistivity usingan R-CHEK™ RC2175 meter (Electronic Design to Market, Toledo, Ohio) andfor percent transmittance and haze according to ASTM D1003 using aHAZE-GARD PLUS Hazemeter (BYK-Gardner, Columbia, Minn.). These resultsare summarized in Table I.

Example 3 (Comparative)

Table II shows corresponding results for a PET substrate (“PET”), apolyurethane matrix coated on a PET substrate and polyurethane(“PU/PET”), silver nanowires deposited from an aqueous dispersion onto aPET substrate (“AgNW/PET”), and a silver nanowire in polyurethane layerwhich had been coated on a PET substrate (“AgNW/PU/PET), which werepresented in Example 2 of European Patent Publication EP1965438, whichis hereby incorporated by reference in its entirety.

TABLE I Transmission Haze Resistivity Sample (%) (%) (ohms/sq) Example 183.0 9.38  60 Example 2 89.0 5.22 110 GORILLA 2317 93.2 0.15Non-conductive Substrate CORNING 93.2 0.53 Non-conductive MicroscopeSlide

TABLE II Transmission Haze Resistivity Sample (%) (%) (ohms/sq) PET 91.60.76 Non-conductive PU/PET 92.3 0.88 Non-conductive AgNW/PET 87.4 4.7660 AgNW/PU/PET 87.2 5.74 60

There is described a transparent conductive film comprising: (a) aflexible glass substrate; and (b) at least one conductive layer disposedon the flexible glass substrate, the at least one conductive layercomprising at least one metal nanoparticle.

In an embodiment, the flexible glass substrate has an average thicknessless than about 500 μm, or an average thickness less than about 150 μm.

In an embodiment, the flexible glass substrate has an average thicknessgreater than about 10 μm and less than about 100 μm.

The flexible glass substrate can achieve a radius of curvature greaterthan about 5 mm and less than about 50 cm without breaking.

The flexible glass substrate can achieve a radius of curvature greaterthan about 10 mm and less than about 10 cm without breaking.

In an embodiment, the flexible glass substrate comprises anion-exchanged glass.

In an embodiment, the flexible glass substrate comprises at least one ofa silicate glass, an alkali silicate glass, an alkali aluminosilicateglass, an aluminosilicate glass, a borosilicate glass, an alkalialuminogermanate glass, an alkali germanate glass, or an alkaligallogermanate glass.

In an embodiment, the at least one metal nanoparticle comprises at leastone nanowire, nanocube, nanorod, nanopyramid, or nanotube.

In an embodiment, the at least one metal nanoparticle comprises at leastone nanowire.

In an embodiment, the at least one metal nanoparticle comprises at leastone coinage metal.

In an embodiment, the at least one metal nanoparticle comprises silver.

In an embodiment, the at least one conductive layer has a surfaceresistivity less than about 150 ohms/sq, or a surface resistivity lessthan about 65 ohms/sq.

The embodiment can include a total light transmission of at least about80%, or a total light transmission of at least about 85%.

The embodiment can further comprise at least one layer disposed betweenthe flexible glass substrate and the at least one conductive layer.

There is described an article comprising: a transparent conductive filmcomprising: a flexible glass substrate; and at least one conductivelayer disposed on the flexible glass substrate, the at least oneconductive layer comprising at least one metal nanoparticle.

The article can comprise at least one of an electronic display or atouch screen.

The article can comprise comprising a portable telephone, a cellulartelephone, a computer display, a laptop computer, a tablet computer, apoint-of-purchase kiosk, a music player, a television, an electronicgame, or an electronic book reader.

There is also described a method comprising: (a) providing a flexibleglass substrate; and (b) coating the flexible glass substrate with atleast one composition comprising at least one metal nanoparticle.

In one embodiment of the method, the flexible glass substrate isprovided on a roll.

In one arrangement, the coated flexible glass substrate is produced bythe method.

In one embodiment, the method further comprises forming a transparentconductive film from the coated flexible glass substrate.

There is described a transparent conductive film produced by any one ofthe methods described above.

1. A transparent conductive film comprising: a flexible glass substrate;and at least one conductive layer disposed on the flexible glasssubstrate, wherein the at least one conductive substrate comprises atleast one metal nanoparticle and the at least one conductive layerexhibits a total light transmission of at least about 80%.
 2. Thetransparent conductive film according to claim 1, wherein the at leastone conductive layer further exhibits a surface resistivity less thanabout 150 ohms/sq.
 3. The transparent conductive film according to claim1, wherein the flexible glass substrate has at least one of thefollowing: (1) an average thickness less than about 500 μm, (2) anaverage thickness greater than about 10 μm and less than about 100 μm,(3) can achieve a radius of curvature greater than about 5 mm and lessthan about 50 cm without breaking, (4) can achieve a radius of curvaturegreater than about 10 mm an less than about 10 cm without breaking, or(5) comprises an ion-exchanged glass.
 4. The transparent conductive filmaccording to claim 1, wherein the flexible glass substrate comprises atleast one of a silicate glass, an alkali silicate glass, an alkalialuminosilicate glass, an aluminosilicate glass, a borosilicate glass,an alkali aluminogermanate glass, an alkali germanate glass, or analkali gallogermanate glass.
 5. The transparent conductive filmaccording to claim 1, wherein the at least one metal nanoparticlecomprises at least one metal nanowire, nanocube, nanorod, nanopyramid,or nanotube.
 6. The transparent conductive film according to claim 1,wherein the at least one metal nanoparticle comprises at least onenanowire.
 7. The transparent conductive film according to claim 6,wherein the at least one nanowire comprises at least one coinage metalor silver.
 8. The transparent conductive film according to claim 1,further comprising at least one layer disposed between the flexibleglass substrate and the at least one conductive layer.
 9. An articlecomprising the transparent conductive film according to claim
 1. 10. Atransparent conductive film comprising: a flexible glass substrate; andat least one conductive layer disposed on the flexible glass substrate,wherein the at least one conductive substrate comprises at least onemetal nanowire and the at least one conductive layer exhibits a totallight transmission of at least about 80%.
 11. The transparent conductivefilm according to claim 10, wherein the at least one conductive layerfurther exhibits a surface resistivity less than about 150 ohms/sq. 12.The transparent conductive film according to claim 10, wherein theflexible glass substrate has at least one of the following: (1) anaverage thickness less than about 500 μm, (2) an average thicknessgreater than about 10 μm and less than about 100 μm, (3) can achieve aradius of curvature greater than about 5 mm and less than about 50 cmwithout breaking, (4) can achieve a radius of curvature greater thanabout 10 mm an less than about 10 cm without breaking, or (5) comprisesan ion-exchanged glass.
 13. The transparent conductive film according toclaim 10, wherein the flexible glass substrate comprises at least one ofa silicate glass, an alkali silicate glass, an alkali aluminosilicateglass, an aluminosilicate glass, a borosilicate glass, an alkalialuminogermanate glass, an alkali germanate glass, or an alkaligallogermanate glass.
 14. The transparent conductive film according toclaim 1, wherein the at least one nanowire comprises at least onecoinage metal or silver.
 15. The transparent conductive film accordingto claim 14, further comprising at least one layer disposed between theflexible glass substrate and the at least one conductive layer.
 16. Anarticle comprising the transparent conductive film according to claim10.